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Unplugged Roadster, how long is TOO LONG...

OK I know the general consensus is going to be "pull the ESS disconnect" but I have to ask; how much "parasitic drain" will there be on the battery if the ESS disconnect is left plugged in and it is placed into storage starting at about 80% charge (~185 miles)? Are we talking 5% a week, 10% a week? I understand it is highly dependent on temperatures so let me say the temperature in storage will range between 40F and 80F... Not extreme heat which will force it to run A/C to cool the batteries and I'm not sure if the Roadster runs any heating circuit to warm them?

OK I know the general consensus is going to be "pull the ESS disconnect" but I have to ask; how much "parasitic drain" will there be on the battery if the ESS disconnect is left plugged in and it is placed into storage starting at about 80% charge (~185 miles)? Are we talking 5% a week, 10% a week? I understand it is highly dependent on temperatures so let me say the temperature in storage will range between 40F and 80F... Not extreme heat which will force it to run A/C to cool the batteries and I'm not sure if the Roadster runs any heating circuit to warm them?

What does everyone think?

Anyone experienced in the matter?

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I'm guessing few months... as long as the car doesn't wake up it should be fine in that time. Though I've noticed the roadster sometimes has issues going to sleep and it wasn't battery balancing either. I had to turn the key on then back off for it to finally fall asleep. So if it stays awake it will not last long at all.

I just picked up Roadster #249 and it had a charge back in April, and when I got it this week the ESS is in critical state (it's charging now). So less time than that for sure...

First, I will say...I do NOT know the answer; won't even give an uneducated guess.

But, I would also imagine that anyone who DOES have an educated guess would hesitate to give one, considering the consequences of bad advice is a $40K bill (for you).

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Well, one of my goals is to rebuild Roadster battery packs so maybe it is a good opportunity for me anyways! Haha... Obviously, I don't want a bum battery anymore than anyone does, that's a lot of value down the toilet... Just hoping to get a "rough idea", of course there is no guarantee and nothing said on here would I hold anyone liable for...

I'm guessing few months... as long as the car doesn't wake up it should be fine in that time. Though I've noticed the roadster sometimes has issues going to sleep and it wasn't battery balancing either. I had to turn the key on then back off for it to finally fall asleep. So if it stays awake it will not last long at all.

I just picked up Roadster #249 and it had a charge back in April, and when I got it this week the ESS is in critical state (it's charging now). So less time than that for sure...

Click to expand...

I think its likely that #249 was not fully charged in April either, correct? So, 6 months without a "full" start and it at least sounds like it is still alive, that is impressive! I am starting to think the "bricked battery" fear may be a little over-rated, obviously its "healthier" for the vehicle to be plugged in all the time and if its especially hot this is even more critical to run the cooling, but its nice to see that the battery can at least "survive" that sort of abuse, even if it will suffer some degradation...

I'm sure my last Roadster was left unplugged and only partly charged for about 3-5 months, basically every salvaged Roadster would have that happen...

... I think its likely that #249 was not fully charged in April either, correct? So, 6 months without a "full" start and it at least sounds like it is still alive, ...

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Sorry I wasn't very clear, the ESS was to the point where the 12v power supply stopped working, and BMB boards powered down... I had to use my custom tools to start charging the pack at 0.2 Amps, voltage of the ESS pack is now at 245v. But I'm pretty sure I already have a shorted cell in one of the bricks I'll have to disconnect from the rest.

Sorry I wasn't very clear, the ESS was to the point where the 12v power supply stopped working, and BMB boards powered down... I had to use my custom tools to start charging the pack at 0.2 Amps, voltage of the ESS pack is now at 245v. But I'm pretty sure I already have a shorted cell in one of the bricks I'll have to disconnect from the rest.

Click to expand...

Oh, yikes, I'm less impressed now (with Tesla, still impressed with you of course!)

I'm guessing few months... as long as the car doesn't wake up it should be fine in that time. Though I've noticed the roadster sometimes has issues going to sleep and it wasn't battery balancing either. I had to turn the key on then back off for it to finally fall asleep. So if it stays awake it will not last long at all.

I just picked up Roadster #249 and it had a charge back in April, and when I got it this week the ESS is in critical state (it's charging now). So less time than that for sure...

Click to expand...

Spaceballs, do you own 3 Roadsters now? Are you going to make a shot at having the most Roadsters?

In cool temperatures, a standard mode charge will drain to nothing in about three months. In hot temperatures it could be a lot faster, if the circulation pump starts running.

Personally, I would NOT leave a Roadster unattended and not plugged in unless you pulled the ESS disconnect. Frankly even the Storage Mode makes me nervous because it allows the car to drain to a very low state of charge, and if for any reason the car stops topping up you could be in trouble. So I check the car daily when in Storage Mode. If I was going to leave it alone for a week or two when it was in Storage Mode, then I would make sure it was at 50% first.

OK I know the general consensus is going to be "pull the ESS disconnect" but I have to ask; how much "parasitic drain" will there be on the battery if the ESS disconnect is left plugged in and it is placed into storage starting at about 80% charge (~185 miles)? Are we talking 5% a week, 10% a week? I understand it is highly dependent on temperatures so let me say the temperature in storage will range between 40F and 80F... Not extreme heat which will force it to run A/C to cool the batteries and I'm not sure if the Roadster runs any heating circuit to warm them?

What does everyone think?

Anyone experienced in the matter?

Click to expand...

The pack heater does not run unless it is plugged in or turned on (as in driving).

Not all storage situations are the same. For example, when shipping a Roadster it will drain much quicker than in your garage because certain types of motion will trigger the car to turn on.

Sorry I wasn't very clear, the ESS was to the point where the 12v power supply stopped working, and BMB boards powered down... I had to use my custom tools to start charging the pack at 0.2 Amps, voltage of the ESS pack is now at 245v. But I'm pretty sure I already have a shorted cell in one of the bricks I'll have to disconnect from the rest.

Click to expand...

What was the voltage of the ESS when you started? It will be interesting to see how well that ESS recovers considering the damage from such a low discharge.

So, Roadster #114 has been on US soil for about 3 weeks now, stuck in customs due to an incompetent customs agent (didn't realize customs shouldn't be paid on a US manufactured vehicle). Anyways, it made its journey across the Atlantic and hasn't been plugged in for about 5 weeks at this point, I was told by the ground transport company who now has the car that it is sitting about "half full" with 95 miles of range remaining... By the way, it has been in Newark, NJ, I'm assuming its been cold up there (just FYI)...

Glad to see the Roadster pack is holding up fine on its journey and excited that it is only about a week away from being HOME!

Reviewing the logs today since the car finally arrived home! So update; on 11/04/2015 the car was driven to South Hampton from London, on arrival at the port it was at 68% SOC, on 12/22/2015 when it arrived to my house in Phoenix, AZ it was at 47%, so 21% lost in its journey across the Atlantic and across the USA over the span of about 48 days, not bad at all! Much better than I thought it would be...